Fedora 33 Qt crash


after upgrading to F33 a third party package using Qt crashes at start (worked fine in F32)

with some help from the packager/maintainer - it seems as if it is Qt that crashes (both under wayland and xcb)

the issue linked above does contain a backtrace, and the analysis points towards the following:
" In both cases, the call stack starts at the QtSingleApplication constructor, and the crash is in Qt, when emitting QScreen::screenAdded from QWindowSystemInterface::handleScreenAdded .

  • This is the first thing which is called from main .
  • Maybe qcad, qgis do not use QtSingleApplication .

So all I know is it is Qt + Fedora + QtSingeApplication."

I personally lack the skills to dig further without instructions - should i file a bug ? and in that case against what package ?

is there a fedora qt package that also uses the same qt function that i can test ?